Former Tesla PR man Daryl Siry’s Wired.com Autopia columns are always good for some interesting insights on the EV world… as long as you take them with the grain of salt that Siry’s status as “advisor” to EV startup Coda Automotive demands. This week Siry has it in for the mass-market EV frontrunner, the Nissan Leaf, accusing its makers of “cutting corners” and “overpromising” range specs. According to Siry:
First, Nissan overpromised on the realistic range by consistently quoting a number tied to the most optimistic benchmark, the LA4 cycle. Drivers who stick to stop and go traffic on city streets in temperate climates may indeed consistently see 100 miles of range, but most drivers will see significantly less in a mix of city and highway driving. Driving in California, the country’s top market for electric vehicles, involves a lot of time on highways where the 65 mph speed limit is rarely observed. The LA4 cycle Nissan quotes mostly stay below 30 mph with one two-minute “sprint” at 55 mph every 22 minute cycle.
But wait, there’s more!
It also appears Nissan has cut corners on the most critical aspect of electric vehicle technology – the battery pack. The key engineering tradeoff Nissan has made is opting not to include active thermal management, where the temperature of the pack is controlled by an HVAC system similar to what cools the passenger cabin on a hot day. Instead, Nissan has opted to use only an internal fan that circulates the air within the sealed pack to evenly distribute the heat, which escapes by passive radiation through the pack’s external case.
We don’t need thermal management for the U.S., but we are looking at the technology for Dubai and other locations like that… We’ve gone on the record saying that the pack has a 70-80 percent capacity after 10 years… If it wasn’t our pack and it wasn’t our engineers and we weren’t working on it for 17 years… we wouldn’t make the statement